Locating users inside a building, store, mall, airports, and the like, within a high-level accuracy is a well known problem in the industry. Traditional techniques for locating a wireless communication device within an environment include received signal strength indications (RSSI), time difference of arrival (TDOA), angle of arrival, etc. However, these techniques all suffer from a lack of accuracy, i.e. accuracy is on the order of 60-100 feet. This is not sufficiently accurate for an indoor environment.
In addition, present location techniques are subject to interference due to reflections off of metal surfaces, i.e. multipath.
Hence, there is a need of a technique to provide the ability for more accurate locationing of a device within an indoor environment. In particular, it is desirable to provide indoor locationing accuracy to within three to four feet, i.e. within an aisle of a store for example.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.